The present invention relates to rotary compressors and their method of assembly wherein the vane slot is prevented from being distorted during the welding operation of the compressor cylinder to the compressor outer metal casing.
Rotary compressors include a hermetic outer metal casing in which there is disposed a refrigerant compressor unit having an angular chamber or compression chamber defined within a cylinder. Disposed for rotation within the chamber is a roller which is driven by an eccentric formed as an integral part of a drive shaft extending from a motor. The cylinder has a radial vane slot open at one end into the chamber and has disposed therein a vane which is spring biased into engagement with the roller thereby dividing the chamber into a low and high pressure side. It is important for compressor efficiency and noise reduction that the tolerances of the vane slot be held to a minimum. During assembly of the compressor the cylinder is placed inside the metal casing and a welding operation through the outer case joins the casing to the cylinder. During the welding operation and subsequently during cooldown distortion forces are set up which, if not controlled, will distort the vane slot and adversely affect the minimum tolerance dimensions of the vane slot thereby detrimentally affecting the efficiency of the rotary compressor and the introduction of noise during the compressor operation.
By this invention there is provided a rotary compressor and method of assembly that prevents distortion of the vane slot as a result of the welding operation of the casing to the cylinder.